app.js

const TelegramBot = require('node-telegram-bot-api');
const request = require('request');

// replace the value below with the Telegram token you receive from @BotFather
const token = '765967396:AAHp8wOEmBhyl4wQo1pA2L-1jFy8Ws0tpCo';

// Create a bot that uses 'polling' to fetch new updates
const bot = new TelegramBot(token, {polling: true});

// Matches "/echo [whatever]"
bot.onText(/\/curse/, (msg, match) => {
  // 'msg' is the received Message from Telegram
  // 'match' is the result of executing the regexp above on the text content
  // of the message

  const chatId = msg.chat.id;
  // const resp = match[1]; // the captured "whatever"

  // send back the matched "whatever" to the chat
  bot.sendMessage(chatId, 'Какая валюта вас интересует', {
    reply_markup: {
      inline_keyboard: [
        [
          {
            text: '€ - EUR',
            callback_data: 'EUR'
          },
          {
            text: '$ - USD',
            callback_data: 'USD'
          },
          {
            text: '₽ - RUR',
            callback_data: 'RUR'
          },
          {
            text: '₿ - BTC',
            callback_data: 'BTC'
          }
        ]
      ]
    }
  });
});

bot.on('callback_query', query => {
  const id = query.message.chat.id;

  request('https://api.privatbank.ua/p24api/pubinfo?json&exchange&coursid=5', function (err, response, body) {
    const data = JSON.parse(body);
    const result = data.filter(item => item.ccy === query.data)[0];
    const flag = {
      'EUR': '🇪🇺',
      'USD': '🇺🇸',
      'RUR': '🇷🇺',
      'UAH': '🇺🇦',
      'BTC': '₿'
    };
    let md = `
    *${flag[result.ccy]} ${result.ccy} 💱 ${result.base_ccy} ${flag[result.base_ccy]}*
    Buy: _${result.buy}_
    Sale: _${result.sale}_
    `;
    bot.sendMessage(id, md, {parse_mode: 'Markdown'});
  });
});

// // Listen for any kind of message. There are different kinds of
// // messages.
// bot.on('message', (msg) => {
//   const chatId = msg.chat.id;

//   // send a message to the chat acknowledging receipt of their message
//   bot.sendMessage(chatId, 'Received your message');
// });


//https://github.com/yagop/node-telegram-bot-api
//https://api.privatbank.ua/#p24/exchange